1. Field of the Invention
The present invention relates to a pneumatic nebulizer valve assembly for use in ventilators or like apparatus and, more specifically, to a permanent in-line tee valve particularly suited to deliver medication to patients who are ventilator dependent.
2. Description of the Prior Art
A nebulizer is a pneumatically, or an electrically powered device that nebulizes or atomizes medications, at a particulate droplet size, to be delivered through an opening in the top of the nebulizer into a tee which is attached to the end of the ventilator circuit. The medication is then delivered through the ventilator tubing to the air passages of the patient. Conventionally, the tee is attached to the top of the nebulizer and placed in series within the ventilator circuit.
Presently, a patient on a ventilator may have to be completely taken off the ventilator for a brief time to initiate breathing treatment. This renders the circuit open, creating a situation that is potentially hazardous to both the patient and the staff. A control valve for restricting fluid flow through the nebulizer or for isolating the nebulizer from the rest of the ventilation circuit would not require the patient to be taken off the ventilator. One example of a control valve is shown in U.S. Pat. No. 4,281,652, issued Aug. 4, 1981 to Donald M. Miller. The control valve, referred to as a closable port, has a rebreathing bag connected thereto and is closable by a closure member. It is not clear how the closure member functions.
A valve apparatus is shown in U.S. Pat. No. 4,267,832, issued May 19, 1981 to Taisto Hakkinen, having an adjustment ring rotatably mounted over an exhalation valve. The exhalation valve has a front portion with an aperture or an exhalation port therein. The adjustment ring has an aperture provided therein which is movable over the front portion of the exhalation valve through the rotation of the adjustment ring. The adjustment ring is rotatable so that the aperture in the adjustment ring can be located in an overlapping relationship to the exhalation port located in the front portion of the exhalation valve. Unlike Hakkinen, applicants' instant invention is a T-shaped valve having an inner sheath supported by an outer sheath. The inner and outer sheaths each include an aperture. The apertures may be selectively aligned and misaligned through a rotational displacement of the inner sheath relative to the outer sheath to control fluid flow through the valve.
A tee valve assembly is described in U.S. Pat. No. 5,062,419, issued Nov. 5, 1991 to Donald L. Rider. The tee assembly includes a tee shaped based outer tube having a rotary valve control tube or inner tube therein. A bore in the tee shaped based outer tube includes a horizontal pipe and a shorter vertical pipe. The horizontal pipe includes a hole in communication with the vertical pipe. The inner tube includes a radial opening. The radial opening in the inner tube is alignable with the hole in the horizontal pipe by rotating the inner tube with respect to the horizontal pipe. A novel feature of applicants' invention is that the inner sheath remains substantially within the confines of the outer sheath. Another novel feature is that the outer sheath includes a circumferentially disposed opening passing therethrough and the inner sheath includes a control knob extending therefrom which passes through the opening in the outer sheath. The control knob is displaceable within the opening in the outer sheath to shift the inner sheath relative to the outer sheath. Neither of these features is shown in the Rider patent.
None of the above patents, taken either singly or in combination, is seen to describe the instant invention as claimed.